mmc: sdhci-acpi: Disable write protect detection on Acer Aspire Switch 10 (SW5-012)

On the Acer Aspire Switch 10 (SW5-012) microSD slot always reports the card
being write-protected even though microSD cards do not have a write-protect
switch at all.

Add a new DMI_QUIRK_SD_NO_WRITE_PROTECT quirk which when set sets
the MMC_CAP2_NO_WRITE_PROTECT flag on the controller for the external SD
slot; and add a DMI quirk table entry which selects this quirk for the
Acer SW5-012.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200316184753.393458-2-hdegoede@redhat.comSigned-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/sdhci-acpi.c

@@ -80,6 +80,7 @@ struct sdhci_acpi_host {
 
 enum {
 	DMI_QUIRK_RESET_SD_SIGNAL_VOLT_ON_SUSP			= BIT(0),
+	DMI_QUIRK_SD_NO_WRITE_PROTECT				= BIT(1),
 };
 
 static inline void *sdhci_acpi_priv(struct sdhci_acpi_host *c)
@@ -671,6 +672,18 @@ static const struct dmi_system_id sdhci_acpi_quirks[] = {
 		},
 		.driver_data = (void *)DMI_QUIRK_RESET_SD_SIGNAL_VOLT_ON_SUSP,
 	},
+	{
+		/*
+		 * The Acer Aspire Switch 10 (SW5-012) microSD slot always
+		 * reports the card being write-protected even though microSD
+		 * cards do not have a write-protect switch at all.
+		 */
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Aspire SW5-012"),
+		},
+		.driver_data = (void *)DMI_QUIRK_SD_NO_WRITE_PROTECT,
+	},
 	{} /* Terminating entry */
 };
 
@@ -795,6 +808,9 @@ static int sdhci_acpi_probe(struct platform_device *pdev)
 
 		if (quirks & DMI_QUIRK_RESET_SD_SIGNAL_VOLT_ON_SUSP)
 			c->reset_signal_volt_on_suspend = true;
+
+		if (quirks & DMI_QUIRK_SD_NO_WRITE_PROTECT)
+			host->mmc->caps2 |= MMC_CAP2_NO_WRITE_PROTECT;
 	}
 
 	err = sdhci_setup_host(host);